The goals of this project are to identify and determine the function of varicella-zoster varus (VZV) genes that are expressed during latency and active infection. We have shown that VZV DNA is present in human trigeminal ganglia recovered at autopsy by using the polymerase chain reaction (PCR). RNA transcripts corresponding to immediate-early and early VZV genes have been detected in human trigeminal ganglia using in situ hybridization and Northern analysis. At present, we are further characterizing VZV RNA transcripts in human trigeminal ganglia by using Northern analysis, by reverse transcription of the RNA followed by PCR amplification, and by construction of a cDNA library from human trigeminal ganglia RNA. We have previously identified VZV proteins that transactivate or transrepress other viral genes. We are constructing cell lines that stably express these VZV proteins and will analyze the effect of these proteins during infection of the cells with VZV or herpes simplex virus. In addition, we are constructing VZV mutants which are deleted for the genes encoding transactivation proteins, a transrepression protein, or viral glycoproteins.